Department
of Orthodontic Edited DR. J. A. SALZMANN,
All communications ante of articles
Anodontia
Abstracts
and Reviews
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by NEW
YORK
CITY
Concerning further information about abstracted material and the XCWt01‘ books for consideration in this department should be addressed to .Dr. J. -4. Salzmann, 664 Madison Avenue, New York City
in Hereditary Ectodermal Dysplasia: By Ralph E. McDonald, J. Heredity 40: 9598, April, 1949. Patient’s EIGtory.-Miss J. IS., 4 years, white, presented for an examination Oct. 31, 1947. The parents were concerned about their daughter’s lack of normal complement of teeth and the unusual morphology of those teeth present. The mother related that pregnancy was uneventful and the baby was full term. At birth there was an absence of hair and a skin eruption was observed and diagnosed as eczema. The first teeth erupted at 10 months and the remaining teeth present seemed to come in “all at once. ” Physical Examination.--Au oral and physical examination revealed features characteristic of an ectodermal dysplasia. Hypotrichosis was evident to a mild degree, several bald areas being noted on the child’s scalp. From the parents it was learned that the patient was suffering from anhidrosis or an abnormal deficiency of sweat. During the summer months the daughter was unable to play outdoors without becoming overheated and obtained relief only after retiring to a cool place. The outstanding ectodermal deficiency was noted in the dentition of t,he child. From an oral and radiographic examination the following teeth were noted : Upper denture : Permanent teeth--central incisors, right cuspid, and first molar. Deciduous teeth-central incisors, cuspids, and right second molar. Lower denture : Permanent teeth-central incisors. Deciduous teeth-central incisors and left cuspid. The incisors and cuspids were conical and peg-shaped. The hair of the patient was dry and the skin dry and scaly. This can be explained by an absence or scantiness of the sebaceous secretion (aseatosis). A report from the attending physician at birth ruled out the possibility of congenital syphilis. There are a number of secondary features often associated with an ectodermal dysplasia, several of which could be demonstrated in this case. There was a deficiency in the salivary flow, the lips were protuberant, and the patient presented a saddle-nosed appearance which seems to be typical in patients suffering from an ectodermal dysplasia. Family Histon-y.--Tt was impossible to examine the grandparents of the patient, but so fa,r as could be determined they were free from any symptoms of ectodermal dysplasia. The father had a full complement of teeth and other ectodermal structures were normal. Oral radiographic examination of the mother revealed the ul)pet* right srcontl and third molars to be congenitally missing. Her teeth were free of dental caries and she hacl’ never undergone any dental operations. A son, aged 5, was unaffected, and oral roentgenograms !I)14
ABSTRACTS
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REVIEWS
945
failed to demonstrate an absence of teeth. Upon questioning the father concerning possible relationship between him and his wife, it was learned that his grandmother and his wife’s mother were cousins. Two types of Mendelian heredity are commonly recognized in which the gene may be dominant or recessive. In either case the gene may or may not be sex-linked. The hereditary character of the anomaly (ectodermal dysplasia) has been generally accepted as being sex-linked recessive and rarely seen in females. Rushton reported a case in which the dysplasia did not behave as a sex-linked character. A mother and son had varying degrees of anodontia but no other female relatives were known to be affected. Cerny observed a 12-year-old female with anodontia whose ancestors, brothers, and sisters were free from abnormalities of the teeth. Weech recorded a case of a white girl, aged ‘i, with anodontia. An older brother and sister and the parents were free from anomalies similar to those of the patient. Anodontia, like color blindness, may be inherited as a sex-linked recessive character. The gene for it is transmitted from an affected man to all his daughters because it is in his X chromosome. These daughters will be normal although heterozygous because the gene for anodontia is recessive and is dominated by the corresponding normal gene in their other X chromosome. However, half of their sons by a normal man will receive an affected X chromosome from their mother and will have the defect. In contrast to a sex-linked inheritance, a recessive gene in some other chromosome may be transmitted through several generations and the defect may not be evident. Cousin (consanguineous) marriages in a family which is carrying the recessive gene may bring this anomaly to the surface. In order for ectodermal dysplasia to occur in the female, the affected person would have to inherit two affected chromosomes, one from each parent, and a degree of inbreeding makes this situation much more likely. To summarize, a case of anodontia in the female is reported. The heredity in this case is of an incompletely recessive character. The complex abnormality (ectodermal dysplasia) is evident in the daughter and a slight deficiency in the dentition is noted in the mother. An older brother and the father of the patient are unaffected. Information from the parents indicates that no other members of the family are affected. The mother and father of the patient are distant cousins.
Multum
in Parvo: By L. Russell Marsh, F.D.S., R.C.S. (Eng.), D. Record 69: 120-128, May, 1949. There are expert technicians who regard patients merely as impersonal objects of their craft, not as human beings at all. These fellows ought to be building motor cars. Orthodontics is more than a technical job, more than a biologic study; it is a human responsibility, not only for the successful conclusion of a case, but also for the comfort and happiness of a child during and after treatment. With our skill we can change a child’s whole outlook on life, but the real importance of that success is to the child’s happiness, not to our records. I would lay particular emphasis upon the personality of the child and his background. Either you are going to make friends with that child, or you are going to have an uphill fight all the way, with a good possibility of failure, whatever your technical competence and however easy a case it may be. l?ortunately, youngsters are very ready to make friends and, generally speaking, are quite prepared to like you, provided that they have no cause t,o mistrust you. Fortunately, again, our work is not usually painful. But it is